Question

I know this can be done by:

1. Comparing hour and minutes etc..
2. Comparing date.getTime() % 86400000
3. comparing date.toLocaleTimeString()

is there a straight forward way?

Answer 1

If you want to compare just the time component, you can do:

function isTimeEqual(d0, d1) {
  return d0.getHours() == d1.getHours() &&
         d0.getMinutes() == d1.getMintues() &&
         d0.getSeconds() == d1.getSeconds() &&
         d0.getMilliseconds() == d1.getMilliseconds();
}

You may not care about the milliseconds.

If you know that daylight saving is never observed at the location, or the times are UTC, you could do:

var msPerDay = 24*60*60*1000;
return d0 % msPerDay == d1 % msPerDay;

or

return !((d0 - d1) % 8.64e7);